Oxidase Subunit Research Articles

DNA barcode reference library of the fish larvae and eggs of the South China Sea: taxonomic effectiveness and geographic structure

Fish early-stages constitute useful indicators of the states of marine ecosystems, as well as important fishery resources. Given the spectacular phenotypic changes during ontogeny, and the paucity of diagnostic morphological characters at the species level, the identification of fish early-stages is a challenging task. DNA barcoding, the use of the mitochondrial gene of the cytochrome c oxidase subunit I (COI) as an internal species tag, opened new perspectives for the identifications of both larval fish and fish eggs. However, the accuracy of the identifications assisted by DNA barcoding are dependent of the completeness of the DNA barcode reference libraries used to assigned unknown sequences to known species. Here, we built a DNA barcode reference library for 113 species of larval fish and 85 species of fish eggs involving the production of 741 newly generated DNA barcodes from South China Sea (63 localities). Together with 514 DNA barcodes mined from Genbank for 116 species from the South China Sea regions, a reference library including 1255 DNA barcodes for 308 species (248 locations) was assembled. The present study emphasizes the importance of integrating DNA barcoding to large scale inventories of early stages, as DNA-based species delimitation analyses delimited 305 molecular operational taxonomic units (MOTUs) and multiple cases of discordance with morphological identifications were detected. Cryptic diversity is detected with 14 species displaying two MOTUs and a total of 23 species were lumped into 11 MOTUs due to low interspecific divergence and/or mixed lineages.

DNA barcode identification of a tropical liver fluke (Fasciola gigantica) in cattle from Oyo, southwestern Nigeria

BackgroundFascioliasis is a major parasite illness that affects ruminants, both domesticated and free, and has an impact on public health and animals’ productivity. The genetic diversity of Fasciola species in cattle from Oyo, Oyo State, Nigeria is yet not well understood. In this study, the genetic diversity of Fasciola gigantica in slaughtered cattle in Oyo was examined using a molecular-based approach targeting the mitochondrial cytochrome C oxidase subunit I (COI) gene region.ResultsOne hundred flukes were gathered from slaughtered cattle, and their COI gene sequences were analyzed using maximum likelihood methods. The results of phylogenetic analysis showed genetic similarities between Nigerian F. gigantica and isolates from Algeria, Egypt, Iran, Sudan, China, Japan and Nigeria. The predominant DNA substitution was the A to T transversion, while the least common substitution was the G to A transition.ConclusionOur results show how useful the COI gene region is for examining intraspecific differences between F. gigantica isolates. The genetic similarity observed among the sampled F. gigantica populations suggests the value of mitochondrial DNA sequences as a marker for the accurate identification and characterization of Fasciola species across different ruminants.

First report of Angiostrongylus vasorum in an African golden wolf (Canis lupaster) in Algeria

BackgroundAngiostrongylus vasorum, commonly known as the “French heartworm,” is a nematode belonging to the Metastrongyloidea superfamily. This parasite was first identified in Toulouse, France in 1853 infecting the pulmonary arteries and the right side of the heart of a Pointer dog. Angiostrongylosis is an important infection due its severe clinical signs and potential for causing high morbidity and mortality in domestic dogs. This nematode has not been studied in Algeria. The aim of this study was investigate the presence of lungworms among different mammal species in a number of Algerian regions.MethodsBetween February 2022 and September 2023, 47 road-killed animals were collected from six administrative units (departments) in Algeria. All carcasses underwent a full parasitological necropsy, and lung tissues were preserved in 10% buffered formalin and concentrated ethanol for further study. All collected samples were subjected to histological and PCR (cytochrome c oxidase subunit 1 gene) analyses for lungworm identification.ResultsHistological examination revealed the presence of nematode eggs and larvae in the alveolar space and chronic obstructive vascular changes were detected in a single golden African wolf (Canis lupaster) collected from the department of Constantine. First-stage larvae were collected and morphologically identified as Angiostrongylus spp. The molecular identification confirmed the presence of A. vasorum. All other animals tested were negative for lungworms.ConclusionsTo the best of our knowledge, this is the first report of A. vasorum infection in an African golden wolf (Canis lupaster). We report a new host association, highlighting the importance of further studies to update the geographical distribution of A. vasorum and its epidemiology across Algeria.Graphical

Impact of potential biomarkers, SNRPE, COX7C, and RPS27, on idiopathic Parkinson's disease.

Parkinson's disease (PD) is a progressive neuro-degenerative disorder most common in older adults which is associated with impairments in movement and other body functions. Most PD cases are classified as idiopathic PD (IPD), meaning that the etiology remains unidentified. To identify key genes and molecular mechanisms to identify biomarkers applicable to IPD. We applied a bioinformatics approach using a gene expression in whole blood dataset to pinpoint differentially expressed genes (DEGs) and pathways involved in IPD. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of DEGs were subsequently performed. A protein-protein interaction (PPI) network was then constructed to select hub genes that may influence IPD. We further investigated the levels of differentially methylated regions (DMRs) and differentially expressed microRNA (DEMs) of whole blood of patients with IPD to validate hub genes. Additionally, we examined the hub gene expression patterns in the substantia nigra (STN) using single-cell RNA sequencing datasets. In total, we identified 124 DEGs in the blood samples of patients with IPD, with GO and KEGG analyses highlighting their significant enrichment. Analysis of PPI networks revealed three major clusters and hub genes: small nuclear ribonucleoprotein polypeptide E (SNRPE), cytochrome C oxidase subunit 7C (COX7C), and ribosomal protein S27 (RPS27). DMRs and DEMs analyses revealed hub gene regulation via epigenetic and RNA interference. In particular, SNRPE and RPS27 showed identically regulated gene expression in the STN. This study suggests that SNRPE, COX7C, and RPS27 in whole-blood samples derived from patients may be useful biomarkers for IPD.

NEW RECORD SPECIES OF GIANT FRESH WATER SHRIMP FROM THE DOWNSTREAM OF SERAYU RIVER

Indonesia is characterized by great diversity of freshwater shrimp, consisting of several islands due to the geographical location on the equator. A recent investigation conducted in Central Java has identified Serayu River as the major habitat of freshwater shrimp genus Macrobrachium. Therefore, this research aimed to determine the type of giant freshwater shrimp found downstream of Serayu River using explanatory method. The experiment was conducted for one year (January - December 2023) and the results found two freshwater giant prawn species, namely Macrobrachium rosenbergii and Macrobrachium spinipes. Moreover, this research is the first record of M. spinipes based on the Cytochrome C oxidase Subunit I (CO1) gene. The mtDNA segment of M. rosenbergii was 631 bp (base pairs) (GenBank accession: LC813231.1), while M. spinipes was 616 bp (GenBank accession: PP735157.1). M. spinipes and M. rosenbergii downstream of Serayu River showed similar locations and characteristics. Genetic distance conducted on 15 species of the genus Macrobrachium showed that giant freshwater prawn serayu had a matrix value of 0.09 - 0.18. Genetic analysis conducted with GenBank indicated that M. spinipes showed significant differences from other species, suggesting the natural dispersal of juvenile through currents across Wallace Line. This research also found that M. rosenbergii was similar to M. dacqueti and related to M. malcolmsonii, while M. spinipes was close to M. suphanense. To support these results, recommendation was made to explore further the rivers in the western part of Java, Indonesia.

The female and emended male description of the USA Interior Highlands endemic Allocapnia oribata Poulton & Stewart, 987 (Plecoptera: Capniidae)

The female of Allocapnia oribata Poulton & Stewart, 1987 is newly associated by tree- and genetic distance-based phylogenetic methods using the mitochondrial cytochrome c oxidase subunit I gene barcode fragment sequence data. The first description of the female and an emended description of the male of A. oribata are presented. Supporting data includes color images, scanning electron micrographs, and genetic analysis of DNA barcodes. Corrections to the holotype and paratype localities are presented with the help of B.C. Poulton. Additional notes on the phylogeny and endemism of Allocapnia Claassen, 1928 are provided.

Morpho-molecular characterization and phylogenetic relationships of Encotyllabe percussa n. sp. (Monogenea: Capsalidae) from the spangled emperor Lethrinus nebulosus (Teleostei, Lethrinidae).

Encotyllabe percussa n. sp. is proposed based on morphology and DNA sequences analysis of ribosomal (18S, 28S) and mitochondrial (COI) gene fragments. Encotyllabe percussa n. sp. was found infecting the spangled emperor Lethrinus nebulosus (n = 75) with higher prevalence from Dibba, Musandam (Gulf of Oman) than in Dhofar Salalah (Indian Ocean), Oman (p = 0.03). The general morphology of E. percussa n. sp. resembles E. caballeroi, E. chironemi and E. spari, which exhibit pre-equatorial testes. However, E. percussa n. sp. shows unique morphological characteristics distinguishing from congeneric species: the large hamuli bear notch allocated externally between the first half proximal of the root, and the small hamuli exhibit semicircular shape with undivided roots. Phylogenetic relationships within the Encotyllabe genus remain unresolved. However, the tree topology with the 28S showed overall consistency with the principal component analysis arrangement (PCA) derived from the morphological analysis. Which showed that the large and small hamuli, marginal hooks, ovary, testes (length and width) and peduncle are currently the most important morphological traits within the genus. Cytochrome c oxidase subunit I (COI) gene fragment showed high interspecific genetic divergence adding unambiguous resolution to discriminate/designate species identity. Interrelations within the genus support the identity of Encotyllabe percussa as a new species. This is the first species characterized with three gene fragments, the second congeneric species described in L. nebulosus and the first recorded in Oman.

Gene Sequencing Study of Mitochondrial Cytochrome Oxidase Subunit I (COI) in Aedes aegypti Mosquito

Aedes aegypti is an important vector from the public health point of view. It transmits pathogens of Dengue and various other diseases. Controlling vector populations is key to reducing disease transmission and it is possible by understanding the taxonomic characteristics of the vectors and their genetic analysis helps in the identification of the genetic variations in species of different geographical areas. The main aim of the present study is the screening of the Aedes mosquito genome of local species as genetic studies give some insights into the vaccine for the treatment of the diseases caused by mosquito species. In the present study, the adult Ae. aegypti collected from Suryapet town where Dengue fever is endemic, used for the mitochondrial Cytochrome Oxidase subunit I (COI) gene sequencing using the techniques of polymerase chain reaction, Electrophoretic separation, spectrophotometric analysis, and BLAST. The mitochondrial COI sequence of 583 bps is published in the National Centre for Biotechnology Information (NCBI) with accession number ON413769. The sequence data was matched with the database available in the NCBI to identify variation in the gene as this gene keeps changing in the organisms and may contribute to the species establishing itself in a particular region due to congenial environmental conditions. One match with the protein called haem copper oxidase subunit I. The transmission of different pathogens in different areas can be ascertained by comparing similar sequence studies documented. Genomic studies involving genetic markers are of immense help in developing the vaccine. The mitochondrial COI gene is the marker often used for evolutionary research. The single nucleotide polymorphisms (SNP) or Restricted fragment length polymorphisms (RFLPs) that occur in DNA also contribute to the vector's adaptability to the different geographical areas and also the survival benefit which are the basis for understanding the vectors thoroughly and their role in disease transmission.

Genetic Variation in the Invaded Population of the Fall Armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), in India

The fall armyworm, Spodoptera frugiperda, an invasive, polyphagous pest, causes significant damage to corn. The majority of insects rely on a broad range of digestive enzymes and an intricate detoxifying mechanism to consume chemically diverse host plants. The genetic variation in S. frugiperda was analyzed using cytochrome oxidase subunit I (COI) and triose phosphate isomerase (Tpi). In addition, a new attempt was made to determine the variation with respect to two detoxifying genes, viz., carboxylesterase and glutathione S-transferase. The highest genetic variation (3.03%) was found between the S. frugiperda populations of Tirupati and Delhi with respect to the Tpi gene and between the populations of Punjab and Hosur regarding COI (3.30%). The results for various genes revealed that populations of the fall armyworm were homogeneous, showing low genetic distance using COI, ranging from 0.40 to 3.30%, and, using Tpi, ranging from 0.43 to 3.03%. The variation in carboxylesterase and glutathione S-transferase ranged from 0.04 to 0.15% and from 0.01 to 0.02, respectively. Amino acid sequences were also produced using DNA sequences from several fall armyworm populations. Populations in Tirupati, Solapur, and Hyderabad shared 98.7% of their sequence with that in Delhi. Fall armyworm amino acid sequences showed 79.7 to 82.0% identity with S. exigua and 69.6 to 73.0% identity with S. litura. Our study provides vital information for understanding the genetic variation in the fall armyworm following its invasion of India.

A new species of Buresilia (Opiliones, Phalangiidae) from Turkey

A new harvestman species, Buresilia gumushanensis sp. nov. (Opiliones: Phalangiidae), is described based on male specimens collected from Gümüşhane province, Turkey. Detailed descriptions, diagnostic features and pictures of the new species are provided, together with mitochondrial cytochrome c oxidase subunit I (COI) sequences. The phylogenetic tree constructed using the COI gene region revealed the phylogenetic position of the genus Buresilia within the family Phalangiidae. In addition, the new species is compared with known species of the genus Buresilia.

A new species of Thoracophelia (Annelida, Opheliidae) from the Yellow Sea of South Korea.

Thoracophelia Ehlers, 1897 is a genus of Opheliidae characterised by the body divided into three distinct regions, modified parapodia in chaetiger 10 and a ventral groove restricted to the posterior half of the body. To date, 18 species have been described in the genus. Amongst them, six species have been recorded in northeast Asia. A new species, Thoracopheliafoliformis sp. nov., was discovered in the intertidal zone of the Yellow Sea, South Korea. This is the first Thoracophelia species report from the Yellow Sea. This new species is closely related to T.dillonensis (Hartman, 1938) from California and T.ezoensis Okuda, 1936 from Japan in having pectinate branchiae. However, the new species can be distinguished from the two species by the unique combination of the following characteristics: 15 pairs of wrinkled pectinate branchiae with 12-15 filaments at best development and a foliaceous mid-ventral plate in the pygidium instead of one or two thick ventral cirri. Detailed descriptions and illustrations of T.foliformis sp. nov. are provided. Sequences of the mitochondrial cytochrome c oxidase subunit I (COI), nuclear 18S ribosomal DNA (rDNA) and 28S rDNA of the new species were determined and analysed.

A new species of the pill millipede genus Rhopalomeris Verhoeff, 1906 (Diplopoda, Glomerida, Glomeridae) from Myanmar, and notes on Rhopalomeriscarnifex (Pocock, 1889).

The taxonomy of the pill millipede genus Rhopalomeris Verhoeff, 1906, which is restricted to Indochina and currently comprises six described species, is refined and updated. An integrative taxonomic approach was employed that combines morphological examination with DNA barcoding using the cytochrome c oxidase subunit I (COI) gene for species identification and delineation. The first objective was to confirm the identity of Rhopalomeriscarnifex (Pocock, 1889), a charismatic species known as the "candy pill millipede" due to its vivid coloration, based on specimens collected near the type locality in Myanmar. The second objective was to describe a new species, Rhopalomerisnigroflava Likhitrakarn, sp. nov., discovered in Linno Gu, Kayin State, Myanmar. This new species is distinguished by its small body size (5.1-9.7 mm long) and yellow body with contrasting brown to blackish markings on certain terga. In addition, the position of the telopod syncoxital lobe relative to the lateral syncoxite horns separates it from other Rhopalomeris species. The interspecific divergence between R.nigroflava Likhitrakarn, sp. nov. and other congeners ranges from 10.85% to 16.13%, based on uncorrected COI p-distances, while the intraspecific divergence was 0%-7.44%. A distribution map of and a revised identification key to all known species of Rhopalomeris are also provided.

Nasopharyngeal Botflies Oestrus ovis and Cephenemyia stimulator in Roe Deer (Capreolus capreolus) from Northern Spain.

Two of 19 roe deer (Capreolus capreolus) in northern Spain were infested with Cephenemyia stimulator and one individual with Oestrus ovis. Three larvae of O. ovis were recovered from the nasopharynx of an adult female deer examined in February 2017, during the hunting season in the province of Burgos. The larvae were identified by morphology, and DNA sequencing from cytochrome oxidase subunit I and 28S rDNA confirmed the identification of both species of larvae. The possibility of O. ovis parasitizing roe deer should be considered in the diagnosis of nasal bots in cervids.

Characterizing spatial patterns among freshwater fishes and shrimps of the Poso River (Sulawesi, Indonesia) using DNA barcoding

Fish biodiversity assessments are vital for understanding threats and aquatic ecosystem health. In the Poso River, Central Sulawesi, changes in biodiversity are influenced by habitat alteration, non-native species, and overfishing. This study evaluates fish and crustacean biodiversity in the Poso River system to address these challenges for improving fisheries management, conservation, and fish passage integration into hydropower development. The present biodiversity study utilized a comprehensive methodology that encompassed both traditional taxonomic approaches and DNA barcoding, specifically targeting the mitochondrial cytochrome c oxidase subunit-1 (COI) gene for accurate species identification and spatial boundary validation. The survey was conducted in the upstream, hydropower area and downstream areas of the river. We found 27 species of fish in the Poso River, including both native (e.g., Anguilla celebesensis, Oryzias nebulosus, Rhyacichthys aspro) and non-native species (e.g., Melanochromis auratus, Amphilophus trimaculatus, Oreochromis niloticus). Two International Union for Conservation of Nature (IUCN) red listed endangered species were also observed (e.g., Adrianichthys poptae and Mugilogobius sarasinorum). DNA barcoding was performed to examine species spatial boundaries. The fish population in the Poso River was dominated by non-native species, accounting for 85.70% of the total population. The upstream reaches had the highest fish abundance and diversity, while the downstream reaches had the lowest. There was, however, no significant difference in species richness and diversity across different locations and seasons. The dominance of non-native species in the Poso River necessitates the improvement of existing fishways within the hydropower dams potentially through the development of selective technology that can block the distribution of these non-native species. This research highlights the critical issue of non-native species proliferation and the potential threat they pose to native fish populations, providing valuable insights for conservation and management efforts in Indonesia and similar ecosystems worldwide.

A new species of the thorid shrimp genus Lebbeus White, 1847 (Decapoda: Caridea) from the Amami Rift hydrothermal vent field in the Ryukyu region, Japan

A new species of the thorid shrimp genus Lebbeus White, 1847, is described and illustrated on the basis of two specimens collected from the recently discovered Amami Rift hot vent field in the Ryukyu region in southwestern Japan, at a depth of 628 m. Lebbeus parvirostris sp. nov. is morphologically similar to L. microceros (Krøyer, 1841), L. mundus Jensen, 2006, L. saldanhae (Barnard, 1947), L. schrencki (Bražnikov, 1907), L. spongiaris Komai, 2001, and L. tosaensis Hanamura & Abe, 2003, but differs from all of them in the lack of a pterygostomial tooth on the carapace in the female. Other diagnostic characters useful in differentiating the new species from the aforementioned close relatives are also discussed. Genetic analyses using sequences of two mitochondrial markers, including cytochrome c oxidase subunit I (COI) and 16S rRNA, are also presented to provide preliminary support for the status of the new species. Lebbeus parvirostris sp. nov. is the second representative of Lebbeus known from active hydrothermal vents in the Ryukyu region.

Irisin improves ROS‑induced mitohormesis imbalance in H9c2 cells.

Abnormal mitohormesis is a key pathogenic mechanism that induces a variety of cardiac diseases, including cardiac hypertrophy and heart failure. Irisin as a muscle factor serves a cardioprotective role in response to cellular oxidative stress injury. Rat cardiomyocyte cells (H9c2) were treated with 40 µM exogenous H2O2 to establish an oxidative stress model, followed by addition of 75 nM exogenous irisin for experiments to determine mitochondrial membrane potential, reactive oxygen species, and Mitohormesis‑related factors by attrition cytometry. Subsequently, the expression of mitochondrial membrane potential, reactive oxygen species and Mitohormesis‑related factors were continued to be determined by establishing a peroxisome proliferator‑activated receptor γ coactivator‑1 alpha (PGC‑1α) siRNA interference model and continuing the treatment with the addition of 75 nM irisin 12 h before the end of interference. When H9c2 cells underwent oxidative stress, irisin partially improved mitochondrial membrane potential and reactive oxygen species levels and partially restored mitochondrial energy metabolism by upregulating fusion proteins optic atrophy 1 (OPA1) mitochondrial dynamin‑like GTPase and mitofusin 2 and downregulating fission protein dynamin‑related protein 1. Following interference with PGC‑1α, irisin promoted mitochondrial biosynthesis by increasing the mRNA levels of OPA1 and protein levels of cytochrome c oxidase subunit 4. These results suggested that irisin acted partially independently of the PGC‑1α signaling pathway to regulate mitohormesis imbalance due to oxidative stress and maintain energy metabolism by improving mitochondrial structure.

Electroacupuncture Slows Experimental Myopia Progression by Improving Retinal Mitochondrial Function: A Study Based on Single-Cell RNA Sequencing.

This study aimed to establish a complete atlas of retinal cells in lens-induced myopia (LIM) and electroacupuncture (EA) intervention by single-cell RNA sequencing (scRNA-seq) and to explore the potential mechanism of EA in improving experimental myopia progression in guinea pigs. scRNA-seq is used to assess changes in individual cellular gene levels in the retina of LIM- and EA-treated guinea pigs. In addition, the role of EA in slowing myopia progression by improving retinal mitochondrial function is further investigated. scRNA-seq identified ten cell clusters in the retina of LIM and EA guinea pigs and mitochondrial respiratory chain-related genes in Cones and Muller-glia cells-Cytochrome oxidase subunit III (COX3), NADH dehydrogenase subunit 4 (ND4), and NADH dehydrogenase subunit 2 (ND2) are closely related to lens-induced myopia. A comprehensive atlas in the retina of LIM and EA guinea pigs at a single-cell level is established, and the positive role of EA in improving retinal mitochondrial function to slow the experimental myopia progression in guinea pigs is revealed.

Genetic diversity and species prevalence revealed by Mitochondrial COI- DNA sequence of thrips population in cotton

Aim: To elucidate the population genetic diversity and species prevalence of thrips on cotton. Methodology: Thrips species were identified utilizing both mitochondrial cytochrome oxidase subunit I (COI) sequence analysis and morphology-based keys. Results: Thrips palmi Karny, Thrips hawaiiensis (Morgan), Ayyaria chaetophora Karny, Scirtothrips dorsalis Hood and Rhipiphorothrips cruentatus Hood identified from collected samples. The distribution analysis revealed that T. palmi stands out as the most abundant and prevalent species, constituting a substantial majority (74%) and occupying a pervasive presence across most cotton-growing locations. The phylogenetic analysis, relying on COI sequences, clearly categorized these five species into four distinct major clades. T. hawaiiensis and R. cruentatus were placed within the first clade, while the second clade featured Scirtothrips dorsalis. The third clade comprised the abundant T. palmi, and the fourth clade accommodated A. chaetophora. Interpretation: The study highlighted genetic diversity of five species of thrips, accentuating the emergence of T. palmi as a dominant pest in cotton, an observation not previously reported. Key words: Cotton thrips, Genetic diversity, MtCOI, Phylogenetic analysis, Species prevalence

Morphometric trait normalization, cluster analysis and molecular phylogenetic analysis in delimiting sympatric Neolissochilus hexastichus and N. hexagonolepis in Umngi River, Meghalaya (India)

Aim: To assess the ability of an integrative approach comprising multivariate morphometric data analysis and mitochondrial cytochrome oxidase subunit I (CO I) sequence divergence analysis in delimiting sympatric Neolissochilus hexastichus (McClleland, 1839) and N. hexagonolepis (McClleland, 1839) mahseer populations in River Umngi, Meghalaya. Methodology: Authoritative descriptions of mahseers were referred during the sampling of 40 individuals from River Umngi, Meghalaya. Multivariate morphometric data were normalized with respect to standard length. The normalization procedure maintained the particular shape factor for each sample. Normalised data were subjected to hierarchical clustering on principal components Analysis (HCPC) for grouping samples according to morphometric features. Genetic affinities based on CO I sequence divergence were assessed by Bayesian Inference (BI) and Automatic Barcode Gap Discovery (ABGD) protocols. Results: The normalization protocols removed the variations in traits due to body size effects and facilitated the identification of allometric traits. HCPC analysis revealed morphometric features that had a significant impact on clustering. Nine N. hexagonolepis and 13 N. hexastichus individuals were identified by integrative morphological and molecular phylogenetic approach. The remaining 18 individuals had incongruence in their memberships in the morphometric and phylogenetic clusters. Interpretation: The integrative approach, apart from delineating N. hexagonolepis and N. hexastichus congeners, highlighted the need to include nuclear genetic markers in future studies for confirming the presence of natural hybrids in sympatric populations of Neolissochilus mahseers. Key words: Cluster, Morphometric, Neolissochilus, Normalization, Phylogenetics

First Molecular Identification and Prevalence of Sarcocystis spp. in Sheep Intended for Human Consumption in Shanxi Province, China.

Sarcocystis species are intracellular coccidian protozoans that can infect a range of animals and humans and cause public health problems and economically significant losses. Sarcocystosis in sheep (Ovis aries) can cause abortion, neurological symptoms, and even death and results in significant economic losses to the livestock industry. To date, however, it is yet unknown whether sheep in Shanxi Province, north China, are infected with Sarcocystis spp. The purpose of this study was to investigate the prevalence of Sarcocystis spp. in sheep in Shanxi Province. Thus, 582 muscle samples of sheep were purchased from farmers' markets from ten representative counties in Shanxi Province, north China, and examined for the presence and prevalence of Sarcocystis spp. by PCR amplification of the mitochondrial cytochrome c oxidase subunit I (cox1) gene. Of the examined 582 mutton samples, 197 samples (33.85%) were Sarcocystis-positive and were sequenced. Of the obtained 197 cox1 sequences, 196 sequences showed nucleotide similarity of 98.56-99.81% with those of S. tenella, and the remaining one cox1 sequence showed nucleotide similarity of 99.71% with that of S. arieticanis. Two representative cox1 sequences of S. tenella (accession nos. PQ189447 and PQ189448) have 99.52% and 99.61% identity with S. tenalla (KC209725) and S. tenalla (MK419984), respectively. The sequence of S. arieticanis (accession no. PQ165949) obtained in this study has 99.71% identity with S. arieticanis (MK419975). This present study documents the occurrence and prevalence of Sarcocystis spp. in sheep in Shanxi Province for the first time, which enriches the data on the distribution of Sarcocystis spp. in sheep in China and has implications for the control of sheep sarcocystosis.